Re: i915 hangs after 201612251500Z changes

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Tue, 10 Jan 2017 18:36:28 +0100
    From:        Riccardo Mottola <riccardo.mottola%libero.it@localhost>
    Message-ID:  <8987c646-9906-77c1-1ad9-e4be6c5a3471%libero.it@localhost>

  | I have i915 and tried building a kenel today.. and it still works, 
  | without applying any patches.
  | i915 has issues for me and they are still there, but it is not worse 
  | than before.

To clear up any lingering issues, the problem in question had nothing
particular to do with i915 (or any other graphics hardware), it was a low
level memory mapping issue that (sometimes) affected (mostly) the message
buffer (which explains both why dmesg failed to work in one reported case,
and resets in others) (in other scenarios all would have been fine.)

i915 may have been related in two ways .. one its presence might alter the
way the BIOS presents the memory map to the OS, and second, I assume (total
guess) it needs to allocate memory itself for its frame buffer (or whatever
the modern equivalent is) and that might (sometimes) have not worked properly.

Certainly nothing in the fix would have any effect on any problems with i915
graphics, or anything related.

kre